The present invention relates to a clamping-type tensile force measurement device for measuring a tensile force of a belt being used to lash a cargo.
It has been known that safe transportation of cylindrical cargoes such as drums, pipes, and shafts requires these cargoes to be lashed with a certain tensile force during transportation. It is therefore necessary to firmly fasten a belt, which secures the cargoes, to a deck or any other appropriate place by using a lashing device or similar apparatus before transportation.
For example, a tensile force measurement device for cargo rope is known from Japanese Unexamined Patent Publication No. H01-162123. This tensile force measurement device is incorporated in a portion of cargo rope, and measurement of a tensile force of the cargo rope is implemented in parallel with lashing a cargo to, for example, a platform using a lashing device. It has also been known to provide the function of displaying tensile force to a lashing device itself having a handle for gradually tightening a belt.
However, according to these known techniques, such a tensile force measurement device or a lashing device having the function of displaying tensile force needs to be incorporated for each cargo. Therefore, these techniques are inapplicable to transportation of a large amount of cargo, such as transportation by ship or boat.
On the other hand, Japanese Unexamined Patent Publication No. S62-9245 (see, in particular, FIG. 3) and Japanese Unexamined Patent Publication No. H09-5181 describe different measurement devices. These devices include three rotatable rollers, and a belt is clamped between the three rollers, thereby measuring a tensile force of the belt.